[Immunohistochemical study of thymidine phosphorylase in uterine cervical intraepithelial neoplasia]

Studies have shown that thymidine phosphorylase (TdRPase) activity in various tumors is higher than that in normal tissues. We studied the immunohistochemical localization of TdRPase in uterine cervical intraepithelial neoplasia (CIN) using monoclonal antibody against TdRPase. Sixty-nine patients were studied: CIN 1, 14; CIN 2, 15; CIN 3 (severe dysplasia), 23; CIN 3 (carcinoma in situ), 17. Immunoreactivity for TdRPase was found in 29% of CIN 1, 40% of CIN 2, 70% of CIN 3 (severe dysplasia), and 88% of CIN 3 (carcinoma in situ), showing increasing incidence with the progression of tumor grade. Furthermore, in higher grade tumor, more immunoreactive cells were found with increased intensity of immunoreaction. Both nucleus and cytoplasm of atypical cells showed immunoreactivity in most TdRPase positive cases, while either nucleus or cytoplasm was positive in a few cases. The stromal tissues were negative for the antibody except 3 cases of CIN 3 (carcinoma in situ) in which the stromal tissues adjacent to the tumor was positive. Our data suggest that immunoreactivity of TdRPase in CIN may correlate with the grade of CIN.